Comcast opens up about how it manages traffic

— -- Managing online traffic can be risky stuff. Just ask Comcast.

The cable TV giant came under fire recently when it slowed a "peer-to-peer" transmission of the King James Bible sent as a test by an Associated Press reporter.

At two special hearings held by the Federal Communications Commission — one at Harvard and another last week at Stanford — the company was excoriated for delaying peer-to-peer traffic.

Peer-to-peer transmissions, which account for more than half of all Web traffic, enable computers to snatch music, data and video files from other computers. To assemble one file, a peer-to-peer service can tap into dozens, or even hundreds, of computers around the world.

According to Werner, the transmission slowdown occurred automatically when network congestion started to build in the Boston area, affecting other customers. The King James transmission, which was small, didn't cause the slowdown, he says.

Once traffic loads got too high, he says, Comcast's network automatically took steps to avoid further degradation. The result: Some peer-to-peer traffic, including the AP transmission, got delayed. But it was never blocked, he says. The transmission "showed up. It just took a little longer to get there."

"The only reason you do something like that is to maintain consistent network performance," Werner says.

At the FCC hearings, Comcast was criticized for throttling back peer-to-peer traffic as a network management technique.

"The technique is not unique to Comcast," says Comcast's Bowling.

FCC Chairman Kevin Martin says Comcast should be specific about its bandwidth limitations. "Consumers have to be informed about what they are buying," he says.

Comcast service contracts say "excessive usage" is banned, but no cutoff point is specified. Bowling says there's a good reason for that: "There isn't a specific limit."